Food is often placed in a transparent container that includes a base with an upwardly-opening cavity that holds food and with a lid that closes the cavity. Buyers want to be assured that, after the food was placed in the container as by a clerk at the food store (who often wears plastic gloves to avoid food contamination), that the container has not been opened. There is a possibility that another customer has secretly opened the container enough to taste a bit of the food before closing it (and possibly leaving germs from his/her finger in the food). Potential buyers want to be assured that this has not happened. A container constructed by the container manufacturer that allowed a clerk at a store to easily close the container and lock it closed, and that thereafter clearly indicated to a potential customer whether or not the container has been opened since it was first closed by the clerk, would be of value. The clear indication of tampering is especially useful for containers that hold food, but is also useful for containers that hold many small nonfood items to assure a customer that some of the original items have not been taken.